JPH0932475A - Small-bore excavator capable of making sharp turn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve excavation when making a sharp turn by providing a spline mechanism along the direction of the axis of an excavator, and connecting using a universal joint the portion between time drive source and the drive shaft of a cutter head to a rear shell connected to the rear of the excavator. SOLUTION: To make a sharp turn, a rear gripper is made to abut to a drilled pit wall surface by means of one rear gripper jack 11, and a rear shell 3 is fixed inside the pit. Next, a front gripper mainly expands a gripper located on the opposite side to expansion of the rear gripper, and deflects the excavator (t) side within the gateway. In this case, contact with the pit wall is made in such a way that a deflection angle is formed between the excavator (t) and the rear shell (u). Thereafter, when excavation is performed using a propulsion jack 4, the propulsion jack 4 is expanded to provide the projecting force of a gripper jack 9 such that the front gripper advances while slipping over the pit wall. Therefore, the propulsion jack 4 can excavate by a predetermined stroke as a cutter head 1 advances.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavator for excavating a small-diameter tunnel, and more particularly to a small-diameter excavation capable of excavating a sharp bend with a small diameter. It is about machines.

[0002]

2. Description of the Related Art Conventionally, when a sewer pipe or a communication cable protection pipe (hereinafter collectively referred to as a pipe body) is buried underground in a building or the like, a diameter of about 1 m usually buried underground in a road or the like is usually used. A small pipe with a diameter of about 70 cm is buried from the main pipe to the underground such as a building. In this case, a branch pipe of about 50 m from the main pipe may be buried.
As a construction for burying this branch pipe, if it is a pipe with a gentle curvature, a push pipe construction method or a non-excavation underground burial work by a small diameter excavator has been conventionally performed.

Since this pushing pipe construction method is a construction method in which a tubular body of a predetermined length is pressed from the rear end and is sequentially buried, a large pushing force is required to push through the ground, and if the curvature is not gentle. The resistance increases and it becomes impossible to embed.

Further, the small-diameter excavator is provided inside a rigid excavator in which a cutter head, which is a driven part, and a motor, which is a driving source, are integrated so that there is no relative displacement between them. Since the mechanism that transmits power from the motor to the cutter head is adopted, the excavator diameter becomes large and the excavator body becomes long because of the motor, so the excavator overall length is longer than the excavation diameter. As a result, the radius of curvature of the tunnel to be excavated also becomes large.

Incidentally, as a conventional technique of the excavator capable of performing a bending operation with a large diameter, there is an invention described in Japanese Patent Publication No. 62-32319, but this invention also has no relative displacement of the drive source portion with the cutter head. Since it is provided in the excavator that is a rigid body, it cannot be used for excavation of a small diameter, which is the object of the invention of this application.

On the other hand, in recent years, such pipes are often buried underground in cities. In such cases, underground excavations are avoided by avoiding underground buried objects such as underground foundations such as buildings and bridge piers. The need arises. Moreover, due to such excavation site and geological conditions, the buried pipeline may be constructed with a small radius of curvature, for example, 10 m or less. Therefore, in this case, since it is not possible with the above-mentioned current method of construction and excavator, the ground surface is excavated along the planned piping route to bury the pipe body.

[0007]

However, in the case of excavating the ground surface and burying the pipe body as described above, since the periphery of the building or the like is usually paved with asphalt or concrete, the paved surface is excavated. It is necessary to bury the pipe body after that, and it is also necessary to re-pave after burying. Moreover, when excavating the ground surface, it is necessary to cure it to protect the surrounding structures.

In addition, when opening or cutting a road or the like, it is necessary to temporarily block pedestrians and transportation facilities, set detours, and perform work on the ground. Alternatively, it is necessary to take measures against dust.

[0009] In this way, when the ground surface is cut open and the pipe body is to be buried, a lot of incidental work is required for the burying work, resulting in problems such as an increase in construction cost and a longer construction period. Will end up.

Further, in recent years, construction work for burying only communication cables such as optical cables has increased, and there is a demand for burying a small-diameter pipe body having a diameter of about 30 cm as a pipe body for burying only such communication cables. There is also a demand for an excavator that can excavate while making a sharp turn without excavating such a small diameter.

In view of the above-mentioned problems, the inventions according to claims 1 to 5 of the present application have a small diameter capable of making a sharp bend that can be constructed while making a sharp bend in a small diameter tunnel without excavating a road or the like. For the purpose of providing an excavator, the inventions according to claims 6 and 7 have, in addition to the objects of the inventions according to claims 1 to 5, a small bendable feature that facilitates discharge of excavation chips. A method for providing a caliber machine, claim 8
In addition to the objects of the inventions according to claims 1 to 7, it is an object of the described invention to provide a small-diameter excavator capable of making a sharp bend that prevents collapse after excavation.

[0012]

In order to achieve the above-mentioned object, a small-diameter excavator capable of making a sharp bend according to a first aspect of the present invention is a front trunk portion having a cutter head at a front end, and a front trunk portion which is extendable and retractable. A body having a rear body connected to the rear body, and a rear body connected to the rear of the body so as to be bendable in a radial direction, a drive source for driving the cutter head, the drive source being provided in the rear body. Between the source and the drive shaft of the cutter head,
The present invention is characterized in that a power transmission means that can expand and contract in the axial direction of the excavation body and a connecting means that can bend in the radial direction are provided and connected.

According to a second aspect of the present invention, there is provided a small-diameter excavator capable of making a sharp turn, characterized in that the power transmission means capable of expanding and contracting in the axial direction of the excavation body is constituted by a spline mechanism. is there.

According to a third aspect of the present invention, there is provided a small-diameter excavator capable of making a sharp bend, wherein the connecting means which is bendable in the radial direction of the excavation body is constituted by a universal joint. To do.

According to a fourth aspect of the present invention, there is provided a small-diameter excavator capable of making a sharp turn, in which the expandable power transmission means and the bendable coupling means are provided inside the excavation body. The power transmission means is arranged at the front part and the coupling means is arranged at the rear part.

A small-diameter excavator capable of making a sharp turn according to a fifth aspect is the excavator according to any one of the first to fourth aspects, in which a front gripper is provided in a front trunk of the excavation body and a rear gripper is provided in a rear trunk. It is characterized by being provided.

A small-diameter excavator capable of making a sharp curve according to a sixth aspect of the present invention, according to any one of the first to fifth aspects, wherein the drive shaft of the cutter head is a hollow inner shaft and a predetermined gap is provided between the inner shaft and the hollow shaft. And a hollow portion of the inner shaft and a gap between the inner shaft and the outer shaft are formed in a water supply channel and a drainage channel for draining the drill excavation. It is characterized by that.

According to a seventh aspect of the present invention, there is provided a small-diameter excavator capable of making a sharp bend, wherein the ejecting port for injecting water for draining the excavation from the cutter head side toward the rear of the hollow portion of the inner shaft is provided. It is characterized by being provided.

A small-diameter excavator capable of undergoing a sharp bend according to claim 8 is the small-diameter excavator according to any one of claims 1 to 7, characterized in that a rear pipe for collapsing prevention is provided at the rear part of the rear body so as to be bendable in the radial direction of the body. It is characterized by being connected.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the invention according to this application will be described below with reference to the drawings. FIG. 1 is a side sectional view showing an example of a small-diameter excavator capable of making a sharp bend according to the invention of this application, FIG. 2 is a view taken along the line AA of FIG. 1, and FIG.
-B sectional drawing, FIG. 4 is CC sectional drawing of FIG. 1, and FIG. 5 is a DD arrow view of FIG. It should be noted that although the respective configurations described in detail below are arranged as shown in the cross-sectional views of FIGS. 3 and 4, in the side sectional view of FIG. The drive system is shown below.

As shown in the figure, the body t has a front body 2 having a cutter head 1 having a cutter bit 1a at its front end and a reduced diameter rear portion 2a of the front body 2 fitted therein by a predetermined length. The rear torso portion 3 is connected to the front torso portion 2 by a plurality of propulsion jacks 4 which are rotatably attached to the front torso portion 2 and attached to the bracket 3a of the rear torso portion 3 at the front end so as to extend and contract. ing.

Accordingly, the expansion and contraction of the front torso portion 2 is configured so that the rear part 2a fitted into the rear torso portion 3 is expanded and contracted by the propulsion jack 4, and the front torso portion 2 fitted into the rear torso portion 3 is inserted.
A guide member 5 is provided between and, and the front body 2 is configured to extend and contract on the same axis as the rear body 3. Also,
Relative rotation between the front body 2 and the rear body 3 is prevented by a key (not shown).

A seal member 6 is provided at the front end of the rear body portion 3 to prevent the outside atmosphere from entering, and also between the drive shaft 7 for rotating the cutter head 1 and the front body portion 2. A seal member 8 is provided to prevent an external atmosphere such as muddy water from entering the inside of the machine.

In this example, the front body 2 is provided with a front gripper 10 which expands and contracts laterally with a gripper jack 9, and the rear body part 3 has a rear gripper which expands and contracts laterally with a gripper jack 11. 12 is provided, and by extending these grippers 10 and 12, the front body 2
Alternatively, the rear body portion 3 is fixed at a predetermined position on the pit wall, and the propelling jack 4 is extended / contracted so that the rear portion 2a of the front body portion 2 slides in the rear body portion 3 to advance. . According to the front gripper 10 provided on the front body portion 2 and the rear gripper 12 provided on the rear body portion 3, as shown below, the gripper 10, 12 easily makes a sharp turn due to the expansion and contraction operation thereof. be able to. It is also possible to make a sharp turn by controlling the extension amounts of the plurality of propulsion jacks 4 to control the excavation direction of the excavation body t.

At the rear end t ₁ of this excavation body t, a connecting pin 1
5, the tip u _{1 of the} rear body u is connected so as to be bendable in the radial direction, and these connection parts v are DD in FIG.
As shown in the arrow view, it is configured to be bendable within a range of a predetermined rotation angle α and is connected so as to obtain a deflection angle with respect to the tunnel axis, and the tip u ₁ of the succeeding body u and the excavation body A gap h is provided so as not to interfere with the rear end t ₁ of t. In addition, a flexible cover 14 for preventing invasion of earth and sand or the like is provided at the connecting portion v as shown by a chain double-dashed line.

Further, the drive shaft 7 integrally connected to the cutter head 1 is a bearing 1 provided in the front body portion 2.
5 and 16 are rotatably supported, and a gear 17 is attached to the drive shaft 7 on the outer periphery of a predetermined position. The gear 17 has a pinion shaft 20 supported by bearings 18 and 19 provided on the front body 2 side.
It is in mesh with the pinion 21 of.

The pinion shaft 20 has an inner diameter surface that is splined, and a spline shaft 22 that is splined to mesh with the spline processing is fitted to form a spline mechanism s. In this example, the spline mechanism s constitutes a power transmission means that can expand and contract in the axial direction of the excavation body t. Therefore, according to the pinion shaft 20 and the spline shaft 22 fitted in this way, the rotational torque of the cutter head 1 can be transmitted by the spline mechanism S even when the front body portion 2 is advanced with a predetermined stroke. Therefore, the shafts 20 and 22 can slide while transmitting torque. The power transmission means may have a structure capable of expanding and contracting while transmitting power.

On the other hand, the rear body u is provided with a motor 23 as a drive source, and an output gear 24 of the motor 23 is provided.
Motor-side drive shaft 26 provided with a gear 25 that meshes with
Are rotatably supported by bearings 27 and 28 provided on the rear body u. In this way, the motor 23, which is the drive source, is separated from the excavation body t integrally joined to the cutter head 1 which is the excavation portion so that there is no relative displacement, thereby reducing the diameter of the excavation body t and increasing the machine unit length. Is shortened to make it easier to make a sharp turn.

A universal joint 29 is provided between the front end of the motor-side drive shaft 26 and the rear end of the spline shaft 22 as a connecting means that is bendable in the radial direction of the body t. The universal joint 29 is configured to be bendable between the motor side drive shaft 26 and the spline shaft 22, and is configured to be able to transmit the rotational torque even in a bent state. This connection means
Any structure may be used as long as it can be bent while transmitting power.

In this embodiment, a spline mechanism s which is a telescopic power transmission means and a universal joint 29 which is a bendable coupling means are provided inside the excavation body t.
The spline mechanism s has a universal joint 29 at the front.
Universal joint 2
9 is arranged close to the connecting portion v between the body t and the subsequent body u to reduce the distance from the connecting pin 13, which is a bending point, so that a large displacement does not occur in the universal joint 29 that bends during bending. ing.

Further, in this embodiment, a mechanism for discharging excavation deviation by fluid transportation is provided so that the excavation deviation excavated by the cutter head 1 can be easily discharged. The water supply and drainage for discharging the drilling waste in this fluid transportation is performed by forming the drive shaft 7 in a double pipe structure composed of a hollow inner shaft 7a and a cylindrical outer shaft 7b. The supply hole 1b is provided on the rear surface of the cutter head 1 at the tip of the pipe.
Is provided, the gap x between the inner shaft 7a and the outer shaft 7b is formed in the water supply passage, and the hollow portion y of the inner shaft 7a is formed in the drainage passage.

Moreover, in this example, since the injection port 30 which is opened from the cutter head 1 side toward the rear of the hollow inner shaft y is provided in the front part of the supply hole 1b, the injection port 30 By injecting water at a high pressure, a backward flow of water is formed to facilitate easy discharge of excavation chips.

A seal housing 31 fixed to the front body 2 is provided at the rear of the outer shaft 7b.
The seal housing 31 is provided with a seal member 33 before and after the water supply port 32 from the supply pipe 35, and a seal member 34 is provided at the rear portion thereof, and the seal member 33 seals water on the water supply side. Water on the drain side is sealed by the seal member 34.

A muddy water relay pipe 36 is provided at the rear end of the seal housing 31 and is close to the rear end of the drive shaft 7 so as not to contact the rear end of the drive shaft 7.
1 is connected to the rear end. A mud discharge pipe 37 is connected to the rear portion of the muddy water relay pipe 36, and the excavation waste mixed with the water by the mud discharge pipe 37 is discharged to the rear of the machine. The supply pipe 35 and the sludge discharge pipe 37 are preferably made of a flexible material so that the displacement when the excavation body t is bent can be absorbed. Further, the excavated waste discharged to the rear of the machine is discharged to the outside of the mine by a drainage pump connected to the mud pipe 37 in a space in a vertical shaft portion (not shown).

With such a structure of fluid transportation from water supply to drainage, the excavation scrap taken in from the cutter head 1 is sent from the rotation space of the drive shaft 7 to the fixed space of the sludge pipe 37, and inside the machine. Finally, it is discharged to the outside of the mine.

By the way, the pit wall after excavation by the excavation body t and the succeeding body u is not always self-supporting. Therefore, in this embodiment, as shown in the side sectional view showing the entire excavator of FIG. 6 and the sectional view taken along the line EE of FIG. The following pipe w is connected to the rear part of the following body u by the connecting pin 13, and the following pipe w is configured to advance while preventing the collapse of the pit wall.

Further, between the rear body u and the rear pipe w, a rear end is rotatably connected to a front portion of the rear pipe w, and a piston front end is rotatably connected to a rear portion of the rear body u. The deflection jack 38 is provided, and the deflection jack 3 is provided.
The expansion and contraction of 8 allows the succeeding tube w to be set at a predetermined deflection angle. In this example, the deflection jack 38 allows easy bending, but other configurations may be used. Then, if the succeeding pipes w are successively added to excavate the entire distance, it becomes possible to excavate a tunnel having a small diameter while preventing the collapse of the pit wall. The connecting pipe connected to the rear part of the succeeding pipe w is also connected in the same manner, and the description thereof will be omitted. Further, 39 indicates a pipe for control, hydraulic pressure and the like.

According to the small-diameter excavator T capable of making a sharp turn as constructed above, as shown in FIGS. 8A and 8B, a small-diameter tunnel is excavated to excavate a small-diameter tunnel without excavation. be able to.

That is, the power of the motor 23 is transmitted from the drive shaft 26 on the motor side to the drive shaft 7 through the universal joint 29, the spline shaft 22 and the pinion shaft 20 of the spline mechanism s, and the cutter head 1 is rotated. , The rear gripper 12 (FIG. 4) is brought into contact with the pit wall by the extension of the rear gripper jack 11 to fix the rear trunk portion 3, and the propulsion jack 4 is used to advance one stroke L ₁ from the reduced state L _0. With this, the front body portion 2 can be advanced by one stroke L ₁ while excavating with the cutter head 1. That is, the propulsion jack 4 is moved by one stroke L ₁
When only extended, the cutter head 1 also shrinks to L _T0
And excavation by the same amount of excavation amount L _T1 from spline mechanism s also extending from L _S0 reduced state by a stroke L _S1 of the same amount. In this spline mechanism s, the cutter head 1
While transmitting the driving torque of the above, it slides up to the stroke L _S1 . At the time of this extension, the driving force of the cutter head 1 is reliably transmitted by the spline mechanism s of the spline shaft 22 and the pinion shaft 20, and the excavation body t is bent to form a deviation angle with the succeeding body u. Even if it is generated, it is absorbed by the universal joint 29.

After that, the front gripper 10 (FIG. 3) is brought into contact with the pit wall by the extension of the front gripper jack 9 to fix the front body 2, and the gripper jack 11 of the rear body 3 is contracted. After the rear gripper 12 is separated from the pit wall, the propulsion jack 4 is contracted, so that the rear trunk portion 3 and the subsequent fuselage u connected thereto can be advanced by one stroke L ₁ of the propulsion jack 4. When the reduction force of the propulsion jack 4 is small, the succeeding tube w connected to the succeeding body u (FIG. 6)
The pushing force may be applied from the rearmost part of. Then, after propelling for one stroke, the rear trunk portion 3 is formed by the above method.
After being fixed by the rear gripper 12, the same operation can be repeated in sequence to drive.

In the case of straight excavation, the gripper 1
After 0 and 12 are extended to the equal amount and the excavation body t is set at the center of the gallery, the grippers 10 and 12 are extended to the right and left equal amounts and the above procedure is performed, whereby the straight advance can be performed.

Further, in the excavation chip thus excavated, the water supplied from the machine rear side by the supply pipe 35 is supplied from the supply port 32 to the gap x between the inner shaft 7a and the outer shaft 7b.
And the water is ejected from the ejection port 30 to the rear of the hollow portion y through the supply hole 1b on the rear surface of the cutter head 1, the excavation deviation in the cutter head 1 is accompanied by this water and the inner shaft 7a.
It is discharged through the hollow portion y of the above, and is discharged from the muddy water relay pipe 36 to the rear of the machine through the muddy water pipe 37.

On the other hand, when performing a sharp turn, as shown in the explanatory view of FIG. 9, the rear gripper 12 is brought into contact with the excavated shaft wall p surface by one rear gripper jack 11 (see FIG. 4). The rear body part 3 is fixed in the mine. Then, the front gripper 10 mainly expands the gripper 10 on the side opposite to the expansion of the rear gripper 12, deflects the excavation body t side in the tunnel, and shifts the excursion angle θ between the excavation body t and the subsequent fuselage u. To make contact with the well wall p. After that, when excavating by the propulsion jack 4, the front gripper 10 moves forward while sliding on the pit wall p (see FIG. 3).
When the propulsion jack 4 is extended as a rush output of, the cutter head 1 moves forward and can excavate a predetermined stroke L ₁ of the propulsion jack 4.

During such a sharp excavation, even if the motor 23 and the cutter head 1 are in a biased state having a relative angle, the universal joint 29 keeps the angle .theta. It is possible to excavate a tunnel having a small diameter by extending the stroke up to a predetermined stroke L ₁ while reliably transmitting.

Even in this case, as in the case of the above-described discharge of excavation chips, the water supplied from the rear surface of the cutter head 1 causes the excavation chips to be discharged to the rear of the machine through the inner shaft 7a of the drive shaft 7.

Further, when excavating a tunnel having a certain length and having a predetermined distance, a predetermined number of bendable subsequent pipes w that can cope with a sharp curve excavation are connected to the rear part of the succeeding body u, so that the pit wall is cut after excavation. It won't collapse, and
By adjusting the deflection jacks 38, the tunnels excavated by the excavation body t are connected with the same radius of curvature, and therefore excavation can be performed without causing a large resistance. After the excavator T reaches the front shaft, the main pipe can be installed in the tunnel by connecting the main pipe to the succeeding pipe w and pulling it out from the front shaft. In addition, since this trailing pipe w can be maintained at a predetermined angle by the deflection jack 38, it can be used for another work again and connected to the rear part of the trailing body u at an arbitrary angle.

Therefore, according to the invention of this application, for example, a small-diameter tunnel having a diameter of about 35 cm can be excavated, and non-open burial of a small-diameter pipe body such as a communication cable or a domestic sewer pipe can be performed. It will be possible.

In this embodiment, since the construction by fluid transportation is described as a preferable discharging method of excavation slip, a large device for slip discharge is unnecessary, resulting in a more compact machine and quick Although it is possible to achieve the effect of easily responding to bending, it is also possible to discharge by using a screw conveyor or the like.

[0049]

The invention according to this application has the effects as described above, and therefore has the following effects.

According to the small-diameter excavator capable of making a sharp turn according to any one of claims 1 to 8, the drive source is provided to the following fuselage connected to the rear portion of the excavation body, and the power of the drive source is applied in the axial direction of the excavation body. Since the power is transmitted via the elastic power transmission means and the connecting means that can be bent in the radial direction, the excavator can be formed with a small diameter and the excavator can be shortened in total length, so that the cutter head can be powered even when making a sharp turn. It is possible to perform excavation of a sharp turn without excavation while transmitting.

Particularly, according to the small-diameter excavator capable of making a sharp turn according to claim 2, the power can be reliably transmitted by the spline mechanism while expanding and contracting with a simple structure.

Particularly, according to the small-diameter excavator capable of making a sharp turn according to claim 3, the universal joint can surely transmit power in a bent state with a simple structure.

In particular, according to the small-diameter excavator capable of making a sharp turn according to claim 4, since the connecting means is provided at a position close to the bent portion between the excavating body and the succeeding body, the connecting means can be bent greatly. It is possible to transmit power without the need, and it is possible to configure the connecting means with a small displacement amount.

Particularly, according to the small-diameter excavator capable of making a sharp turn according to claim 5, the excavation body can be easily desired by the front gripper provided on the front trunk and the rear gripper provided on the rear trunk. You can make a sharp turn in the direction of.

Particularly, according to the small-diameter excavator capable of making a sharp bend according to claim 6, the drive shaft of the cutter head formed by the double pipe structure is used to discharge the water for draining excavation inside the cutter head. It is possible to easily discharge the drilling scrap to the rear part of the body of the excavation body.

Particularly, according to the small-diameter excavator capable of making a sharp turn according to claim 7, the water jetted from the jet port causes a flow of water to the rear of the hollow portion of the inner shaft to facilitate the discharge of excavation chips. It becomes possible.

Particularly, according to the small-diameter excavator capable of making a sharp turn according to claim 8, excavation can be performed without collapsing the tunnel excavated by the excavator with the collapsing prevention follower pipe connected to the rear portion of the following fuselage. You can

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of a small-diameter excavator capable of making a sharp bend according to the present invention.

FIG. 2 is a view as viewed in the direction of arrows AA in FIG. 1;

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is a sectional view taken along line CC of FIG.

FIG. 5 is a side sectional view showing an entire embodiment of a small-diameter excavator capable of making sharp bends according to the present invention.

6 is a cross-sectional view taken along the line DD of FIG.

FIG. 7 is a view on arrow EE in FIG.

8 is a drawing showing a state of excavation in the small diameter excavator of FIG. 1, (a) is a side sectional view showing a state before excavation,
(b) is a side sectional view showing a state after the excavation.

FIG. 9 is an explanatory diagram for explaining an operation in a case of making a sharp turn at the time of excavation shown in FIG. 8;

[Explanation of symbols]

 1 ... Cutter head 2 ... Front body 3 ... Rear body 4 ... Propulsion jack 5 ... Guide member 6 ... Seal member 7 ... Drive shaft 8 ... Seal member 9 ... Gripper jack 10 ... Front gripper 11 ... Gripper jack 12 ... Rear part Gripper 13 ... Connection pin 14 ... Cover 15, 16 ... Bearing 17 ... Gear 18,18 ... Bearing 20 ... Pinion shaft 21 ... Pinion 22 ... Spline shaft 23 ... Motor 24 ... Output gear 25 ... Gear 26 ... Motor side drive shaft 27, 28 ... Bearing 29 ... Universal joint 30 ... Injection port 31 ... Seal housing 32 ... Water supply port 33, 34 ... Seal member 35 ... Supply pipe 36 ... Muddy water relay pipe 37 ... Drainage pipe 38 ... Deflection jack p ... Well wall s ... Spline Mechanism t ... Drilling body u ... Subsequent fuselage v ... Connecting portion w ... Subsequent pipe x ... Gap y ... Hollow portion T ... Small diameter excavator α ... Rotation θ ... deviation angle

Claims (8)

[Claims] 1. A tunnel body having a front body portion having a cutter head at a front end thereof, a rear body portion elastically connected to the front body portion, and a trailing body connected to the rear portion of the body so as to be bendable in a radial direction. A body and a drive source for driving the cutter head on the succeeding body, and a power transmission means and a radial direction between the drive source and the drive shaft of the cutter head, the power transmitting means being expandable and contractible in the axial direction of the excavation body. A small-diameter excavator capable of making sharp bends, characterized by being provided with a bendable connecting means. 2. A small-diameter excavator capable of making sharp bends according to claim 1, characterized in that the power transmission means capable of expanding and contracting in the axial direction of the excavation body comprises a spline mechanism. 3. The small-diameter excavator capable of making sharp bends according to claim 1 or 2, wherein the connecting means which is bendable in the radial direction of the excavation body is constituted by a universal joint. 4. A telescopic power transmission means and a bendable connection means are provided inside the excavation body, and the power transmission means is provided at a front portion and the connection means is provided at a rear portion.
A small-diameter excavator capable of performing a sharp turn according to any one of 3 to 3. 5. A front gripper is provided on the front body of the excavation body,
A small-diameter excavator capable of making sharp bends according to any one of claims 1 to 4, wherein a rear gripper is provided on the rear trunk portion. 6. A drive shaft of the cutter head is formed of a double pipe structure composed of a hollow inner shaft and an outer shaft provided with a predetermined gap, and a gap between the inner shaft and the outer shaft. And a hollow part of the inner shaft are formed in a water supply channel and a drain channel for excavation drainage, respectively. Excavator. 7. A small-diameter excavation capable of making sharp bends according to claim 6, wherein an injection port is provided for injecting water for draining excavation from the side of the cutter head toward the rear of the hollow portion of the inner shaft. Machine. 8. A steeply curvable bend according to claim 1, wherein a trailing tube for collapsing prevention which is bendable in the radial direction of the excavation body is connected to the rear portion of the trailing body. Small caliber machine.